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Mr.RC-Cam

Next Generation A/P Camera Controller

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Well, this is my main RC AV plane. It has never glitched so dramatically or so close to me before. The FS8 has a glitch counter. I am using the FMA FS8 Rx with FMA opto isolators, seperate batteries for Rx, video, and motor/esc. The ESC is opto-isolated, it is a Castle HV-85.

No metal shield came with mine. The solder side has a metal plate, but the component side does not. On that subject, do you know if the anti-static bags that come with computer components are effective at blocking Rf?

Thanks.

-dave

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It has never glitched so dramatically or so close to me before.

Adding the OSD ends up tying everything electrically together (flight batteries, R/C gear, video Tx's, and/or cameras, essentially are connected to each other in one way or another). So, existing dormant EMI/RFI sources will have more intimate contact to other parts of the system. The noise is accumlative as well. That is why EMI/RFI problems can be a challenge.

No metal shield came with mine. The solder side has a metal plate, but the component side does not.

The solder side metal plate is the metal shield. It is thin aluminum that is cut to the shape of the board. Between the shield and the PC board is a plastic insulator. The shield is grounded to the OSD board at the main Vreg IC using a single 4-40 machine screw and nut. The screw must be reasonably tight to ensure a good RF ground path.

On that subject, do you know if the anti-static bags that come with computer components are effective at blocking Rf?

Conductive component bags will not do much of anything to reduce RFI/EMI.

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Hi

While trying to diagnose my glitching problem, I bit the bullet and took apart one of my FMA recievers. It has a motorola chip in it with number MC3371D on it. According to the spec sheet, pin 13 is 'meter' which is the same as RSSI.

With Tx off, I get 0.155v and with Tx on and no antenna (but pretty close to me) I get 2.268v and with Tx on and antenna on I get 2.424v So, what should I set my Inspire board to?

Thanks.

-dave

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I'll add a IC table entry for the MC3371 to the next software release. You should probably use the voltage mode for now. Also, the BA4116 is close, so try it to see if it behaves correctly for you.

But, skip connecting the RSSI until you have solved the interference issue. Adding more wires to the R/C Rx will only introduce another variable. Instead, I suggest you simplify the setup so that you can isolate the problem.

BTW, would you mind remeasuring the RSSI with a 47K resistor to ground? I can create a more accurate profile that way.

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Hi,

I got tired of trying to get the glue

out of the way so I opened another rx I had

of the same model but different frequency.

There was hardly any glue so I was able to

trace connetions to pin 12 and found out that

it has a ohm reading of 189k between pin 12

and the batt. signal pin but when I checked

voltage at the signal pin and gnd I got a 1.3 volt

reading that only changed .2 volts when I turned on

or off the tx otherwise it stayed a constant 1.3 volts

regardless of how far the tx was from the rx.

Will this affect how the inspire should be connected?

Thanks

Midwest-Flyer

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I was able to trace connetions to pin 12 and found out that it has a ohm reading of 189k between pin 12 and the batt. signal pin ...

It should be lower (the data sheet suggests that pin 12 to ground will be less than 50K ohms).

when I checkedĀ  voltage at the signal pin and gnd I got a 1.3 volt reading that only changed .2 volts when I turned on or off the tx otherwise it stayed a constant 1.3 volts regardless of how far the tx was from the rx.

There is something odd going on. On the TA31136, the voltage (pin-12 to gnd) will be above 2V with a strong RF carrier, and under .5VDC with no carrier (tx off).

Maybe you are not measuring Pin 12? The IC pin spacing is tight. If this is a traditional design, pin 12 should lead to an external cap that is used during Rx testing. You can connect to the cap. Or, a sewing needle can be used as a IC pin probe while your helper turns the R/C Tx on and off.

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One quick question...I am very interested in this board, but am wondering if it will be pretty much plug and play when it is released commercially? I have some background in electronics, but don't think I am up to the task of decoding/deciphering/modulating things like you beta testers do. :D

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The production board will be ready to use, or nearly so. You'll have to connect your video gear to the provided A/V cable, which will require soldering. If you don't want to use the GPS module I will offer then you will need to create a cable compatible with your GPS.

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Hi,

These traces are very hard to follow :blink:

I did get 20k across pin 12 and gnd.

On this rx I also got 280 millivolts TX off, .636 volts TX on.

It look like pin 12 connects to cap to gnd. and some resistors

which are connected to what looks like a transsistor then to an

IF can. It looks like the best place to connect to is at the IC.

Midwest-Flyer

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It sounds like the external AGC components have attenuated your receiver's RSSI's signal. You'll have to use the voltage mode rather than the bar graph.

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Beta users: The next software release will omit the RSSI IC menu choices. Instead, the user will be able to set the threshold voltages for the signal strength bar graph based on their particular setup. There will be two new menu entries for this, one for the strong signal level, the other for the weak/no signal level. Keep in mind that this special VDC/bargraph field can be used for any voltage that ranges from 0-5VDC. It does not need to be used just for RSSI.

The waypoint navigation was the last thing on the to-do list. It is working well, but I am still tweaking it. The screen has a new text field set that includes steerage markers (turn-to arrows), turn bearing, and distance to waypoint. There is also a waypoint alarm that blinks the upcoming waypoint number during the approach.

The waypoint mode requires a user supplied Geko 201 handheld GPS rather than the standard micro-sized GPS module. All hardware versions (even the very first beta design) have the external GPS port on it. So this feature is backwards compatible. At the moment I am trying to hammer down all the loose ends, so additional information regarding the waypoint features will need to wait a bit.

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Wow! On screen arrows telling you where to fly to??? That sounds like EXACTLY what I've been waiting for! This board is simply amazing. I can't wait for it to be fully ready and released commercially!

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Any sign of a release date yet?

The NTSC board will be released end of May or early June. It mainly depends on when the assembly vendor delivers the stuffed boards. I am updating the documentation this week. Next week I expect to start testing the PAL video version, but this may get delayed if other things (read: things that pay the bills) get in the way.

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I have posted the latest User Manual and Installation Guide for those that want a sneek peek at the feature set. These two docs can be downloaded from here: http://www.dpcav.com/inspire/inspire.htm

If by chance someone reads these, and something goofy is found, please let me know. :)

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That's a really well put together Manual and Installation Guide there. I'm veeery impressed!

And no I didn't spot anything goofy :P

You mentioned that short range recievers should not be used and that only a high quality double conversion reciever would suffice. Does this include the JR R700 running on their ABC and W circuitry? Would an FMA reciever (with copilot) such as the FS8 provide a better solution?

Edited by Jasper

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You mentioned that short range recievers should not be used and that only a high quality double conversion reciever would suffice. Does this include the JR R700 running on their ABC and W circuitry? Would an FMA reciever (with copilot) such as the FS8 provide a better solution?

I don't have any experience with those exact receivers. For sure, the cheap entry level park flyer receivers, like the GWS, Bluebird, and others like them, are not good candidates.

Thanks for looking the manuals over (and the kind feedback).

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Hi,

I have been using the JR R700 rx for my

testing and it has worked well. When the

new firmware is released I will be using

the RSSI connection :D

Mr Rc-Cam I've been reading through the new docs.

This project and product is getting more fun,cool and

flexilble as time goes on :D:D

Thank-you

Midwest-Flyer

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When the new firmware is released I will be using the RSSI connection.

The V3.2 is available. I included an early version of the bootloader into the V3.1 I sent out last month. But just to be sure, if you see a little heart graphic on the copyright screen during boot (lower left corner), then your version is bootloader equipped. {The new bootloader feature allows a user to flash the Inspire system with downloaded software updates. All it takes is a PC, a cable, and a couple minutes.}

The V3.1 bootloader was my first attempt and it works differently than the newer release. So, I'll have to document it just for the small group of V3.1 users. In the meantime, you can send your PIC microcontroller chip to me and I will re-flash it for you.

NOTE: I won't be able to release the bootloader instructions until the its original developer gives me written permission to do so. I'm still having trouble getting in touch with him.

Edited by Mr.RC-Cam

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This project and product is getting more fun, cool and flexible as time goes on. Thank-you.

You are welcome. I'm a bit surprised by all the features that the OSD now supports too. Certainly more than was originally proposed. But, it is only software. :)

BTW, this week marks the one year anniversary of the start of the project. I have a log of all the time spent on hardware/software development, but I don't dare add it up. Ignorance is bliss, as they say.

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I do'nt have a 4-pin header so I have to order.

So I will send the pic to you this time. I thought

time wise it was a horse a piece, but I will have

a cable ready for the future :)

Thanks

Midwest-Flyer

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BTW, would you mind remeasuring the RSSI with a 47K resistor to ground? I can create a more accurate profile that way.

Sorry for the great delay, but I have made some progress. I have purchased 2 new Rf modules (TP-FM) and (TK-FM) on the advice of a guy who makes his own Txs and I am doing new ground checks now with and without video gear attached. I was finally able to solder the wires to the very small legs of an FMA reciever. Now I need to ask a dumb question, did you want the 47k resistor connected from rssi to ground with the voltmeter in parallel to the resistor or the resistor connected to the rssi, then to the meter, and the meter connected to ground in a series. Again, I'm a bit of electronics newbie, so patience please.

post-6-1147724682_thumb.jpg

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